Vice President Joe Biden with son, Beau Biden, in Houston for medical tests

There are many questions surrounding the health of Vice President Joe Biden's son, Beau Biden, who was brought to Houston Monday to undergo medical tests at an undisclosed hospital here. His father is with him but very few other details have been released.

We do know that Beau Biden's family became concerned after the Delaware attorney general felt weak and became disoriented while driving to a family vacation, and he's seeing doctors at the MD Anderson Cancer Center.

Beau has sent out a couple of tweets since yesterday. One tweet had a picture of him and his wife, Hallie, outside a local restaurant.

He tweeted: "Touched by all your well wishes -- thank you. Nice evening in Houston w/ Hallie; will share update when we have it."

Beau Biden suffered a stroke in 2010 so this is not his first health scare.

According to a statement from his office, he arrived here in Houston yesterday for medical testing. The 44-year-old was hospitalized last week after feeling weak and disoriented following a drive to Indiana for a family vacation.

Officials say he was admitted to Northwestern Memorial Hospital in Chicago, and then consulted with his own doctor at Jefferson University Hospital in Philadelphia. He spent the weekend at home in Delaware before coming to Houston. His father, Vice President Joe Biden, is with him.

While it's not clear what Beau Biden's medical situation is, we asked the opinion of neurosurgeon Dr. David Baskin, who operates on brain cancer patients at Houston Methodist Hospital, if Biden does have cancer, would his history of stroke complicate cancer treatment?

"A problem inside the brain could cause dizziness and lightheadedness for many, many reasons. If you add it all together, you'd be concerned that if there's a cancer, it could be in the brain. But of course we don't know," Dr. Baskin said.

Again, at this time, the Biden family has not said what medical problem Beau Biden is facing, although President Obama is said to have offered his prayers to the vice president over the weekend.

Vice President Biden also has a history of serious brain surgeries. He had two brain surgeries three months apart in 1988, to correct two brain aneurysms. An aneurysm is a bulge in an artery. Biden's brain surgeries occurred when he was 45, just a year older than his Son beau is now.

The Bidens were been seen around town Monday night, having dinner together.

Waitress Sandra Giles was working at D'Amico's Italian Restaurant in the Rice Village when members of Biden's Secret Service detail swept through on Monday. Soon, the vice president, his son, and other family members followed. Giles took a photo with the vice president and recounted the moment on Tuesday.

"I was just trying to take a picture as was walking out. But as I was doing that he saw me, he took my camera away and asked his son to take his picture, he was really nice, I didn't expect that at all," she said.